Spoke ruler



FIG. 1 is a view in perspective from the front right side of a spoke ruler showing my new design;

FIG. 1A is a partially enlarged view of FIG. 1;

FIG. 2 is a perspective view from the front lower right side thereof;

FIG. 3 is a perspective view from the front upper left side thereof; and,

FIG. 4 is an end view thereof.

The broken lines in the drawings represent unclaimed environment only and form no part of claimed design. 

CLAIM The ornamental design for spoke ruler, as shown and described. 